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1.
J Environ Sci (China) ; 150: 422-431, 2025 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-39306417

RESUMO

In recent years, the biodegradable plastics has extensively used in industry, agriculture, and daily life. Herein, the effects of two biodegradable microplastics (BMPs), poly(butyleneadipate-co-terephthalate) (PBAT) and polyhydroxyalkanoate (PHA), on soil sulfamethoxazole (SMX) degradation and sul genes development were comparatively studied based on the type, dosage, and state. The addition of virgin BMPs significantly increased soil DOC following a sequential order PBAT > PHA and high dose > low dose. Meanwhile virgin PBAT significantly reduced soil pH. In general, the addition of BMPs not only promoted soil SMX degradation but also increased the abundance of sul genes, with an exception that pH reduction in virgin PBAT inhibited the proliferation of sul genes. The driving effects of BMPs on soil microbial diversity following the same order as that on DOC. Specific bacteria stimulated by BMPs, such as Arthrobacter and two genera affiliated with phylum TM7, accounted for the accelerated degradation of SMX. Intriguingly, UV-aging hindered the release of DOC from BMPs and the reduction in pH, mitigated the stimulation of microbial communities, and ultimately reduced the promotion effect of BMPs on SMX degradation and sul genes proliferation. Our results suggest that more attention should be paid to the proliferation risk of ARGs in the environment affected by BMPs and UV-aging can be employed sometimes to reduce this risk.


Assuntos
Biodegradação Ambiental , Microbiologia do Solo , Poluentes do Solo , Solo , Sulfametoxazol , Sulfametoxazol/toxicidade , Solo/química , Microplásticos/toxicidade , Raios Ultravioleta , Plásticos Biodegradáveis
2.
J Hazard Mater ; 479: 135592, 2024 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-39217930

RESUMO

Microplastics (MPs) are increasingly entering agricultural soils, often from the breakdown of agricultural plastics (e.g., mulching films). This study investigates the effects of realistic MPs from different mulching films: two conventional polyethylene (PE-1 and PE-2) and two biodegradable (starch-blended polybutylene adipate co-terephthalate; PBAT-BD-1 and PBAT-BD-2). MPs were mixed into Lufa 2.2 soil at a concentration range from 0.005 % to 5 % (w/w dry soil), wide enough to reflect both realistic environmental levels and "worst-case scenarios". Effects on Enchytraeus crypticus reproduction over two generations and six important soil properties were studied. PBAT MPs notably reduced enchytraeid reproduction in the F0 generation, with a maximum decrease of 35.5 ± 9.6 % at 0.5 % concentration. F1 generation was unaffected by PBAT contamination. PE MPs had a more substantial reproductive impact, with up to a 55.3 ± 9.7 % decrease at 5 % PE-1 concentration compared to the control, showing a dose-related effect except for 1 %. Both MP types also significantly affected soil water holding capacity, pH, and total carbon. Other soil properties remained unaffected. Our results highlight the potential negative impacts of MPs originating from real agricultural plastics on soil health and raise concerns about the role of agricultural plastics in sustainable agriculture and food safety.


Assuntos
Agricultura , Microplásticos , Reprodução , Poluentes do Solo , Solo , Poluentes do Solo/análise , Poluentes do Solo/química , Microplásticos/toxicidade , Solo/química , Animais , Reprodução/efeitos dos fármacos , Polietileno/química , Oligoquetos/efeitos dos fármacos , Plásticos/química , Poliésteres/química , Amido/química
3.
J Hazard Mater ; 479: 135554, 2024 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-39232354

RESUMO

Achieving circularity in the plastic economy predominantly depends on sourcing higher quality recyclates. Packaging plastic poses a significant challenge as it is often not prioritised for collection or recycling initiatives. The presence of additives, such as printing ink, impedes the quality of recyclates. Considering the volume of packaging plastics and the importance of branding (aesthetics and consumer information), ink removal is a critical pre-treatment step. However, the literature is limited, with only 14 studies exploring de-inking processes. Drawing parallels with the detergent laundering process, surfactants have been widely investigated in plastic de-inking, with cationic surfactants proving the most effective with a de-inking efficiency of up to 100%. However, concerns exist regarding the toxic and hazardous nature of the surfactants and chemicals. The average hazard quotient (AHQ) was developed, which compares de-inking chemicals as one of the key findings. AHQ provides a quantitative proxy for the hazards and toxicities, which are qualitatively presented as part of the globally harmonised system (GHS) classification of chemicals. To drive emerging packaging plastic de-inking, including the development of green surfactants (e.g. gamma-valerolactone), this work enables an informed chemical selection minimising potential hazards (rather than creating more adverse effects in plastic recycling processes) and toxicities from plastic waste, fulfilling the objectives of cleaner plastic waste recycling.

4.
Waste Manag ; 189: 300-313, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39226844

RESUMO

The plastic industry needs to match the recycling goals set by the EU. Next to technological hurdles, the cost of plastics mechanical recycling is an important modality in this transition. This paper reveals how business economic cost calculation can expose significant pitfalls in the recycling process, by unravelling limitations and boundary conditions, such as scale. By combining the business economic methodology with a Material Flow Analysis, this paper shows the influence of mass retention of products, the capacity of the processing lines, scaling of input capacity, and waste composition on the recycling process and associated costs. Two cases were investigated: (i) the Initial Sorting in a medium size Material Recovery Facility and (ii) an improved mechanical recycling process for flexibles - known as the Quality Recycling Process - consisting of Additional Sorting and Improved Recycling. Assessing the whole recycling chain gives a more holistic insight into the influences of choices and operating parameters on subsequent costs in other parts of the chain and results in a more accurate cost of recycled plastic products. This research concluded that the cost of Initial Sorting of flexibles is 110,08-122,53 EUR/t, while the cost of subsequent Additional Sorting and Improved Recycling ranges from 566,26 EUR/t for rPE Flex to 735,47 EUR/t for rPP Film, these insights can be used to determine a fair price for plastic products. For the Quality Recycling Process it was shown that rationalisation according to the identified pitfalls can reduce the cost per tonne of product by 15-26%.


Assuntos
Plásticos , Reciclagem , Reciclagem/métodos , Reciclagem/economia , Custos e Análise de Custo , Gerenciamento de Resíduos/métodos , Gerenciamento de Resíduos/economia
5.
Sci Total Environ ; 954: 176292, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39306139

RESUMO

Disposable e-cigarettes (vapes) are becoming increasingly popular but there are concerns about their impacts on human health, the environment and resource sustainability. A better understanding of these impacts and potential solutions requires characterisation and quantification of the materials and chemicals used in their construction. In the present study we dismantle nine types of popular, single-use vapes and analyse the components by X-ray fluorescence spectrometry and pyrolysis-gas chromatography mass spectrometry. The median dry mass of vapes was about 50 g, and the main material contribution was either plastic (up to about 80 %) or metal (up to about 85 %, and including the battery). Polycarbonate was the principal plastic used in the casing and nylon was always employed in the wick, but a range of other polymers were identified in other components used in wire insulation, sleeving, packaging, bundling and sealing. Various elements, as additives, residues or contaminants, were encountered in these parts that included As, Ba, Bi, Cr, Hg, Pb and Sb. Metal components were constructed of Al (often with Ti), stainless steel or Ni-based alloys (mainly in the coils), but other metals were often incorporated in alloys (e.g., Bi, Pb, W) or were present in trace quantities (including Co and Nb). Common metals in the Al-plastic-laminated Li-ion batteries were Cu, Co, Fe and Ni, but Au, Ba, Hg and Pb were also detected, while additional metals in the Cu-based printed circuit boards included Ag, Al, Ni, Sn, Ti and V, with traces of Ag, Bi, Mn, Nb and Pb present. The presence of toxic or potentially toxic metals in the vapes poses an environmental hazard through leaching after littering or landfilling, while metals within or in contact with the wick raise concerns about transfer to the e-liquid and exposure to the user. The overall material and chemical complexity of vapes presents challenges for safe disposal and component recycling, but the presence of critical elements, like Bi, Co, Nb, Sb, Sn, V and W, has additional implications for resource management.

6.
Chemosphere ; 365: 143393, 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39307466

RESUMO

Plastic plays an important role in agriculture, but its use has become a concerning source of pollution. While new (bio)degradable, alternative plastics are being developed and used as mulching films, their ecological impacts, in particular under field conditions, are not well understood. Furthermore, there is a notable lack of knowledge on how plastic pollution affects soil invertebrate communities. Most existing studies primarily focus on microplastics, often neglecting the impacts of mesoplastics. This study therefore compared the separate effects of two conventional (polyethylene and polypropylene) and two alternative (polyethylene containing biodegradable additives and compostable polylactic acid) mesoplastic films on plant performance (biomass, seed yield) and soil mesofaunal assemblages in a field experiment. The mesoplastics were applied at 0.1% (w/w), prior to soil being planted with Hordeum vulgare (spring barley), which was grown to maturity, for 11 weeks. Generally, there were no measurable differences between the conventional and alternative plastic treatments, however, barley exposed to mesoplastics showed reduced biomass, seed yield, and chlorophyll content, along with increased oxidative stress. Soil fauna, particularly Collembola, had lower richness and abundance when exposed to both plastic types, but assemblage structure and composition remained unchanged after 11 weeks. This study is pivotal in highlighting that both conventional and alternative plastics can similarly affect plant health and soil ecosystems. The evidence provided is essential for refining future risk assessments of agricultural plastic pollution and underscores the urgent need for more sustainable practices and materials in agriculture.

7.
Microsc Res Tech ; 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39315562

RESUMO

Microplastics (MPs) are small pieces of plastic that are widely distributed in the environment and accumulate within living organisms, so they are the most common types of pollutants at the present time. One of the most widespread types of MP in the environment is polyethylene (PE) MPs. There have been many published studies on the effect of PE MPs combined with other pollutants or chemicals such as benzoanthracene, emamectin benzoate, heavy metals and 4-nonylphenol, on some marine, amphibian, and mouse models. However, research has rarely been conducted on how single-use PE MPs affect the ileum of mammals. The current study is focused on the impact of PE MP exposure with different concentration (6, 60, 600 µg/mL PE/MPs) for 15 days, followed by 15 days of recovery on small intestine(ileum) of C57BL/6 murine model with precision and detail at the cell level by using different technique (histology, histochemistry, immunohistochemistry, and transmission electron microscope). Results demonstrated that the intestinal tissue exhibited nuclear pyknosis, villus deformation, shortness of villi, degeneration of lamina propria, hyperplasia of goblet cells, increase of goblet cells secretion, Alcian blue and Periodic acid-Schiff stain positivity of intact goblet cells, highly significance of P53 immunoreaction expression specially in high concentrations (600 µg/day of PE/MPs) and Ki-67 immunoreaction expression. RESEARCH HIGHLIGHTS: Different doses of microplastics (MPs) induced sever morphological alternations and clinical observations. MPs were deposits in cells and were observed in ultrastructure study. Recovery period able to ameliorate to the most extent the alternations caused by MPs administration.

8.
Nepal J Epidemiol ; 14(1): 1302-1309, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39280642

RESUMO

Bisphenol A (BPA) is widely used around the world in the production of Polycarbonate (PC) plastics. Notably, the ubiquitous 5-gallon water bottles in the UAE are primarily made of PC plastic, making them a significant concern as bottled water is the region's main supply of drinking water. These bottles undergo temperature variations during storage and transportation, potentially leading to harmful BPA (Bisphenol A) leaching. This study analyzed 40 PC 5-gallon water bottles from two local brands A and B, with 20 bottles per brand, under two conditions: room temperature and outdoor sunlight exposure for a month. BPA levels were assessed at 0, 15, and 30 days, following ethical approval. Liquid-liquid extraction and ELISA assays were conducted, with comprehensive kit validation. The results revealed a significant increase in BPA concentration over time, particularly in bottles exposed to elevated temperatures (Day 30 outdoor-stored samples exhibited the highest concentration at 9.05 ± 2.30 µg/L). Brand B consistently exhibited higher BPA concentrations across different samples and environments. This study emphasizes the link between BPA content and storage time, highlighting the need for preventive measures to reduce BPA exposure. Individuals should be aware of potential health risks associated with prolonged storage in plastic containers and consider safer alternatives.

9.
Sci Total Environ ; 953: 176228, 2024 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-39270875

RESUMO

Plastics, encompassing a wide range of polymeric materials, and their downstream products (micro- and nanoplastics, MNPs) are accumulating in the environment at an alarming rate, and they are linked to adverse human health outcomes. Considering that ingestion is a main source of MNPs exposure, the impact of plastics is particularly relevant towards intestinal inflammation and inflammatory bowel disease (IBD). However, the study of MNPs has been limited by obstacles relating to sample collection, preparation, and microplastics analysis based on optical microscopy and chemical analysis, which we detail in this review alongside potential solutions. We summarize available data on human exposure to MNPs and overall health outcomes, with particular focus on data pertaining to intestinal inflammation, microbiome perturbations, and related outcomes. We include ecologic perspectives, and human, in vitro, and animal model studies. We discuss the way forward in MNPs and IBD research, including knowledge gaps and future research.


Assuntos
Doenças Inflamatórias Intestinais , Humanos , Plásticos , Animais , Microplásticos , Nanopartículas , Inflamação , Poluentes Ambientais , Exposição Ambiental
10.
Sci Total Environ ; 954: 176421, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39306119

RESUMO

With the increasing demand for plastics, plastic pollution is growing rapidly. A significant amount of plastic has leaked into the environment, leading to severe environmental issues. Biodegradable plastics are considered promising alternatives to conventional durable plastics, and the environmental impacts of biodegradable plastics have received increasing attention. Poly (butylene adipate-co-terephthalate) (PBAT) is a commercial and cost-competitive biodegradable polymer and has been applied in the packaging and agriculture sectors. The environmental performances of PBAT with second-generation feedstocks from forestry waste have been rarely investigated. Since China is the leading global producer and exporter of PBAT polymer, Chinese cradle-to-gate life cycle inventories of PBAT were compiled in this study. A comparative life cycle assessment (LCA) was conducted to explore the potential for environmental performance of PBAT with second-generation bio-based feedstock compared to fossil-based PBAT and conventional plastics. The results showed that feedstocks contributed to more than 70 % of 18 environmental impact categories of fossil-based PBAT. In comparison, PBAT with second-generation bio-based feedstock reduces the environmental loads in 16 impact categories by 15-85 %, and renewable energy substitution has the potential to reduce environmental impacts by 10 %. Bio-based PBAT performs better than PVC, PP, HDPE, LDPE, and PET in 16 impact categories by 15-80 %. Bio-based PBAT has GWP of 3.72 kg CO2 eq, which is 37 % lower than fossil-based PBAT (5.89 kg CO2 eq) and 18-32 % lower than conventional plastics. Since feedstock dominates the environmental performance of PBAT, the development of biomanufacturing technologies for bio-based polymers and chemicals could significantly improve environmental performance of biodegradable plastics and promote the sustainable development of the plastic industry. Results could serve as the basis for environmental impact and mitigation strategies for biodegradable plastics with bio-based feedstocks, as well as the sustainable development of the PBAT industry.

11.
J Hazard Mater ; 480: 135846, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39303614

RESUMO

Bio-based plastics are marketed as environmentally friendly alternatives to petroleum-based plastics, although they require specific composting conditions for degradation, which leads to their accumulation in the environment and potential risks to aquatic organisms. We hypothesized that the accumulation of bio-based plastics may induce immunotoxic responses in fish. Our research focused on the accumulation and immunotoxicity of 80 nm polylactic acid (PLA) and polystyrene (PS) (0.1-10 mg/L) on early life stage zebrafish (Danio rerio) exposed for 7 days. Compared to PS, there was a higher accumulation of PLA in larvae. Exposure to PLA resulted in a significant increase in neutrophils and macrophages, while immune protein levels such as Complement 3 (C3), Immunoglobulin M (IgM), and C-reactive protein (CRP) were significantly reduced. Furthermore, the mRNA expression of pro-inflammatory cytokines, including tnf-α and il-6, were significantly elevated in PLA treatments. Additionally, PLA-exposed zebrafish were more susceptible to infection by Vibrio parahaemolyticus. Interestingly, at the same concentration, exposures to PS did not induce significant changes in macrophages or immune protein levels, C3 and IgM. This suggests that PLA has a greater immunotoxic response relative to PS. Our research findings contradict the popular belief that bio-based plastics are non-toxic and harmless, which may have potential risk to aquatic organisms.

12.
Artigo em Inglês | MEDLINE | ID: mdl-39307864

RESUMO

Very little information exists on the particle and chemical contamination of consumer (horticultural) composts. In this study, anthropogenic microcellulosics (AMCs), microplastics (MPs) and other microscopic debris, along with anthropogenically impacted metals (Cu, Zn, Pb), have been determined in 12 composts (seven garden composts and five growbags) purchased at outlets in the UK. AMCs and MPs, determined microscopically, were present in all samples at up to about 1100 kg-1 dw. AMCs were more abundant and were dominated by fibres constructed of rayon and cotton, while petroleum-based MPs exhibited a greater diversity in shape and polymeric construction (including polyolefins, polyethylene terephthalate, polyvinyl chloride, resins, paints and rubbers). Other microdebris, present in much smaller concentrations in the composts, consisted of fragments of glass, metal and machined wood and spherical glass beads. Concentrations of the anthropogenically impacted metals, Cu, Pb and Zn, determined directly by energy-dispersive X-ray fluorescence spectrometry, were heterogeneously distributed and averaged 52.4, 192 and 51.6 mg kg-1 dw, respectively. Although concentrations of anthropogenic particles were not related to cost or type of compost, physico-chemical properties or metal concentrations, a significant relationship between Pb content and particle diversity (number of polymers and debris types) was established. This relationship might result from the general contamination of the environment by both Pb and anthropogenic particulates, or the association of the metal with various types of material (e.g. paints, polyvinyl chloride, glass). Despite the ubiquity and diversity of MPs and microdebris in consumer composts, an understanding of their impacts on plant growth, either directly or indirectly (e.g. by interacting with metals), is unknown.

13.
Small ; : e2407262, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39308255

RESUMO

Aqueous Zn-ion batteries are promising and efficient energy storage systems owing to their low cost, high safety, and satisfactory capacity. However, the instability of Zn metal anodes, caused by dendritic growth and parasitic side reactions, hinders their practical application. In this study, a nanophase-separated block copolymer layer that enhances the reversibility of Zn metal anodes is introduced. This layer consists of two components: a high-performance engineering-plastic-based hydrophobic block exhibiting excellent mechanical properties and chemical stability, and a hydrophilic block that significantly improves the interfacial stability of the anode by selectively permeating Zn ions through the separated nanophase channels. Through an improved electrochemical system and scalable fabrication process, this block copolymer provides a feasible approach for the practical application of Zn metal anodes in aqueous energy storage systems.

14.
Artigo em Inglês | MEDLINE | ID: mdl-39311088

RESUMO

INTRODUCTION: The widespread presence of bisphenol-A (BPA) in consumer goods like water bottles and eyeglass frames raises serious concerns about the chemical's ability to accumulate in human tissues. Molecular filtration and activated carbon adsorption are two of the many BPA treatment technologies that have emerged in response to these issues; both are essential in the removal or degradation of BPA from water sources and industrial effluents. CONTENT: To secure the long-term health and environmental advantages of BPA treatment approaches, sustainable development is essential. Both the efficient elimination or destruction of BPA and the reduction of the treatment operations' impact on the environment are important components of a sustainable approach. Different search engines like Pub-Med, MEDLINE, Google Scholar and Scopus are used for these systematic reviews and analyzed accordingly. This can be accomplished by making treatment facilities more energy efficient and using environmentally friendly materials. Greener ways to deal with BPA pollution are on the horizon, thanks to innovative techniques like bioremediation and improved oxidation processes. Reducing dependence on conventional, resource-intensive procedures can be achieved by investigating the use of bio-based materials and natural adsorbents in treatment processes. SUMMARY AND OUTLOOK: This review article tackling the health and environmental concerns raised by BPA calls for an integrated strategy that incorporates sustainable development principles and technology progress. We can reduce the negative impacts of BPA contamination, improve environmental stewardship in the long run, and ensure human health by combining cutting-edge treatment technologies with sustainable behaviours.

15.
Sci Total Environ ; 953: 176017, 2024 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-39236815

RESUMO

The extensive use of plastic products has exacerbated micro/nanoplastic (MPs/NPs) pollution in the atmosphere, increasing the incidence of respiratory diseases and lung cancer. This study investigates the uptake and cytotoxicity mechanisms of polystyrene (PS) NPs in human lung epithelial cells. Transcriptional analysis revealed significant changes in cell adhesion pathways following PS-NPs exposure. Integrin α5ß1-mediated endocytosis was identified as a key promoter of PS-NPs entry into lung epithelial cells. Overexpression of integrin α5ß1 enhanced PS-NPs internalization, exacerbating mitochondrial Ca2+ dysfunction and depolarization, which induced reactive oxygen species (ROS) production. Mitochondrial dysfunction triggered by PS-NPs led to oxidative damage, inflammation, DNA damage, and necrosis, contributing to lung diseases. This study elucidates the molecular mechanism by which integrin α5ß1 facilitates PS-NPs internalization and enhances its cytotoxicity, offering new insights into potential therapeutic targets for microplastic-induced lung diseases.


Assuntos
Endocitose , Pneumopatias , Poliestirenos , Humanos , Poliestirenos/toxicidade , Pneumopatias/induzido quimicamente , Integrina alfa5beta1/metabolismo , Microplásticos/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Nanopartículas/toxicidade
16.
Sci Total Environ ; 953: 176225, 2024 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-39270873

RESUMO

Understanding the stability of NPs in different aqueous environments, related with their size is crucial for assessing their potential risks. This is influenced by several factors, including pH, ionic strength, and the presence of biomolecules, or dissolved organic matter (DOM). In this study, dispersions of NPs derived from common plastic waste materials, including polystyrene (PS), polyethylene terephthalate (PET), polyvinyl chloride (PVC), polymethyl methacrylate (PMMA), and polycarbonate (PC), were synthesized by a nanoprecipitation method with sizes: 189 ± 7, 58 ± 3, 123 ± 4, 151 ± 7 and 182 ± 6 nm, respectively. Stability for a period of 14 days of these NPs was assessed in various natural water matrices. Different analytical techniques were used, including Asymmetric Flow Field-Flow Fractionation (AF4) coupled with UV-Vis and Dynamic Light Scattering (DLS) in series, batch DLS, Fourier-Transform Infrared Spectroscopy-Attenuated Total Reflection (FTIR-ATR), and Transmission Electron Microscopy (TEM). None of the studied NPs was stable in seawater and NPs were transformed in microplastics (MPs) by aggregation. PET was more prone to aggregation in all waters and PS was the most stable followed for PC, PVC and PMMA. However, bottle and tap waters maintained better the original size of NPs. For the most stable dispersion PS, the influence of heteroaggregation in tap and lagoon waters and aging from exposure to UV light in sea water were tested. In both cases, the stability over time was worse for PS. The results can contribute to a more comprehensive understanding of the fate and behaviour of NPs in natural aquatic environments, emphasizing the importance of studying a wide range of polymers.

17.
Talanta ; 281: 126792, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39241645

RESUMO

Determination of olefins in pyrolysis oils from waste plastics and tires is crucial for optimizing the pyrolysis process and especially for the further advanced valorization of these oils in terms of the circular economy. Identifying olefins, even using high-resolution techniques like GC×GC, is challenging without TOF-MS, which allows modification of the ionization step. Currently, the only method for determining olefins in plastic pyrolysis oils is GC-VUV, recently standardized as ASTM D8519. However, TOF-MS and VUV are not affordable instruments for many research teams working on plastics recycling. This paper introduces a simple method for the selective micro-scale adsorption of olefins over AgNO3/SiO2, followed by the GC×GC-FID analysis. Olefins are determined indirectly from the loss of chromatographic area in respective hydrocarbon groups before and after removal. Only 50 µL sample and 15 min of sample separation are needed. Our method was extensively validated and provides a reliable determination of olefin content in a wide range of pyrolysis oils from plastics and tires and their products after mild hydrotreatment. It is affordable to all researchers and industrial companies working on plastics recycling by thermochemical processes as it does not require an MS detector.

18.
Eur Heart J ; 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39240674

RESUMO

Emerging evidence indicates that chemical exposures in the environment are overlooked drivers of cardiovascular diseases (CVD). Recent evidence suggests that micro- and nanoplastic (MNP) particles derived largely from the chemical or mechanical degradation of plastics might represent a novel CVD risk factor. Experimental data in preclinical models suggest that MNPs can foster oxidative stress, platelet aggregation, cell senescence, and inflammatory responses in endothelial and immune cells while promoting a range of cardiovascular and metabolic alterations that can lead to disease and premature death. In humans, MNPs derived from various plastics, including polyethylene and polyvinylchloride, have been detected in atherosclerotic plaques and other cardiovascular tissues, including pericardia, epicardial adipose tissues, pericardial adipose tissues, myocardia, and left atrial appendages. MNPs have measurable levels within thrombi and seem to accumulate preferentially within areas of vascular lesions. Their presence within carotid plaques is associated with subsequent increased incidence of cardiovascular events. To further investigate the possible causal role of MNPs in CVD, future studies should focus on large, prospective cohorts assessing the exposure of individuals to plastic-related pollution, the possible routes of absorption, the existence of a putative safety limit, the correspondence between exposure and accumulation in tissues, the timing between accumulation and CVD development, and the pathophysiological mechanisms instigated by pertinent concentrations of MNPs. Data from such studies would allow the design of preventive, or even therapeutic, strategies. Meanwhile, existing evidence suggests that reducing plastic production and use will produce benefits for the environment and for human health. This goal could be achieved through the UN Global Plastics Treaty that is currently in negotiation.

19.
Heliyon ; 10(16): e36299, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39253233

RESUMO

The world faces an alarming plastic waste problem. The volume of plastic waste is rapidly and continuously increasing, mainly due to the single-use plastics overconsumption, whereas its recycling and utilization leave much to be desired. Despite the negative effects of plastic on the environment and public health, the COVID-19 outbreak shifted the public attention away from the environmental issues, potentially giving space for extended lobbyism by interest groups and industry to delay or even prevent legislation to combat plastic pollution. Our study aims to understand how the media discourse on single-use plastic (SUP) in particular, evolves in the course of the pandemic. How it vary across EU Member States? For this purpose, we specifically analyse plastic-related articles in major prestigious daily newspapers published between June 2019 and June 2021 in four EU Member States: Germany, France, Italy, and Poland, as countries with different levels of sustainable transition to form a representative model of an European context. Additionally, between November 2022 and January 2023, we conducted a series of interviews via Google Meet, with journalists who agreed to be asked on the plastic issues they upraised. Our analysis initially covered 1076 articles, out of which 198 articles were rejected due to non-compliance with the subject or repetition, leaving 878 articles forming the database for eventual analysis. Specifically, we outline a key impact of the COVID-19 pandemic followed by a clear evolution on the number of plastic-related articles, on related stakeholder engagement, and the focus on specific SUP items. Moreover, we address a research gap - presenting a media portrait of different types of SUP in more details and highlighting the significance based on several culturally and linguistically very different countries within a single supranational state (EU). A clear trend reversal towards an informed knowledge circulation across the circular economy model of single-use plastics is ultimately essential to develop sustainable solutions to reject the disposable culture, stop the waste of natural resources, and reduce the consumption of oil or gas for plastic production and thus protect the climate.

20.
Heliyon ; 10(16): e36547, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39258196

RESUMO

Single treatment of metallised food packaging plastics waste (MFPW) has shown disappointing results with recycling rate <20 % due to its complex structure consisting of 10 % aluminium (Al) and 90 % mixed plastic films made of PE, PP, PS, PET, etc. Besides, it is generating many emissions and residues that must be landfilled making it difficult to integrate them into the circular economy. Therefore, a multi-stage recycling (MSR) approach has recently been developed using several sequential mechanical, thermal and chemical processes to recover energy and Al from MFPW with additional revenue for recycling plant operators. The thermal treatment helps to decompose the plastic fraction into wax or oil, gaseous, and solid residue (SR) composed of Al and coal, while the mechanical process can be used as a pre-treatment of MFPW feedstock and SR. Finally, the chemical treatment (leaching and functionalization) can be used to extract Al from SR and to refine coal into carbon microparticles (CPs), respectively. In order to investigate the environmental performance of the proposed MSR system, this research was developed. The investigation was performed using SimaPro life cycle analysis (LCA) tool according to ISO 14040/44 Standards and the impact assessment method is ReCiPe 2016. Five different scenarios were proposed in the constructed LCA layout, namely, conversion of MFPW to a) wax and gas (pyrolysis), b) wax, gas, and aluminium chloride (AlCl3) (pyrolysis and leaching), c) wax, gas, AlCl3, and CPs (pyrolysis, leaching, and functionalization), and d) oil, gas, AlCl3, and CPs (catalytic pyrolysis, leaching, and functionalization). Besides, the oil produced from catalytic pyrolysis is used for generation of electricity (scenario e). The results showed that wax and gas recovery scenario (a) has better environmental potential and environmental benefits compared to incineration practice. The results did not change much after extraction of Al and CPs (scenario b, c), with a few increasing by 2-4% in the total score. While a lot of environmental burdens from upgrading and utilization (Scenario d, e) were recorded, reaching 79 % due to the huge amount of the catalyst was used. Thus, MSR systems have bigger environmental benefits, however, the chemical and catalytic processes still need to be further improved to reduce the effect of terrestrial acidification.

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